<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .box {
        width: 200px;
        height: 200px;
        background-color: rgb(187, 150, 156);
      }
    </style>
  </head>
  <body>
    <div id="app">
      <div class="box" :style="styleObj"></div>
    </div>
    <script src="./vue.js"></script>
    <script>
      const app = new Vue({
        el: '#app',
        data: {
          width: 300,
          styleObj: {
            width: '300px',
            // 如果修改的样式属性名中包含短横线，需要转成小驼峰或者字符串来显示。。。
            // 'background-color': 'pink',
            backgroundColor: 'pink',
          },
        },
      });
    </script>
  </body>
</html>
